Field of the Invention
The present invention relates to a thin film transistor array panel and a manufacturing method thereof.
Description of the Related Art
A flat panel display, such as a liquid crystal display (LCD), an organic light emitting diode (OLED) display, an electrophoretic display, and a plasma display, includes a plurality of pairs of field generating electrodes, with an electro-optical active layer therebetween. The LCD includes a liquid crystal layer as the electro-optical active layer, and the OLED display includes an organic emission layer as the electro-optical active layer. One of the pair of field generating electrodes is generally connected to a switching element to receive an electric signal, and the electro-optical active layer converts the electric signal into an optical signal to display an image.
A display panel with the thin film transistor may be included in the flat panel display. Electrodes of many layers, a semiconductor, and the like are patterned on the thin film transistor array panel, in other words the patterned elements are for producing the thin film transistor array panel, and generally, a mask is used during a patterning process.
Meanwhile, the semiconductor is an important factor to determine a characteristic of the thin film transistor. In such a semiconductor, amorphous silicon is frequently used, but there is a limit to manufacture a high-performance thin film transistor due to low charge mobility. Further, in the case of using polysilicon, due to high charge mobility, the high-performance thin film transistor is easily manufactured, but there is a limit to manufacture a large-sized thin film transistor array panel due to high cost and low uniformity.
Accordingly, researches for a thin film transistor using an oxide semiconductor, which has higher electron mobility and a higher ON/OFF rate of current than amorphous silicon, and has a lower cost and higher uniformity than polysilicon, have been conducted.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.